In permanent magnet synchronous motor,magnetic steel is used to provide magnetic flux,which simplifies the structure of the motor’〖KG-*2〗s rotor and improves the reliability of the motor’ s operation.In addition,because it does not require excitation current,excitation loss is saved and it has the advantages of high efficiency and high power density.However,due to the cogging torque and reluctance torque of the traditional permanent magnet synchronous motor,there is a problem that the output torque of the motor has a large pulsation.Aiming at this problem,taking improving the average output torque of the motor,reducing the output torque ripple of the motor and reducing the total harmonic distortion of the motor air gap magnetic density as the optimization multi-objective,a segmented magnet permanent magnet synchronous motor model was established.The key structural parameters of the motor rotor were taken as the optimized parameters,Taguchi algorithm was used to select the structural parameters that had a greater impact on the optimization goal,then the response surface method was used to fit the optimized target curve to determine the optimal parameter combination,so as to realize the multi-objective optimization for the segmented magnet permanent magnet synchronous motor.The validity was verified by simulation.Finally,a three-phase 48/8-pole prototype was trial-produced and experiments were carried out.The experimental results verify the rationality of the motor structure and optimization method.